Método para Download de arquivo em Java

 /**  
       * Efetua o download do arquivo  
       *   
       * @param pFilePath  
       *      Caminho do arquivo  
       * @param pFileName  
       *      Nome do arquivo  
       * @throws IOException  
       */  
      public static void downloadFile(String pFilePath, String pFileName) throws IOException {  
           String lFileFullPath = pFilePath + pFileName;  
           File lFile = new File(lFileFullPath);  
           HttpServletResponse lResponse = (HttpServletResponse) FacesContext.getCurrentInstance().getExternalContext().getResponse();  
           lResponse.setContentType("application/rar");  
           lResponse.setHeader("Content-Disposition", "attachment; filename=" + pFileName);  
           InputStream lIn = new FileInputStream(lFile);  
           ServletOutputStream lOutput = lResponse.getOutputStream();  
           byte[] buffer = new byte[(int) lFile.length()];  
           int nLidos;  
           while ((nLidos = lIn.read(buffer)) >= 0) {  
                lOutput.write(buffer, 0, nLidos);  
           }  
           lOutput.flush();  
           lOutput.close();  
           lIn.close();  
           FacesContext lFacesContext = FacesContext.getCurrentInstance();  
           lFacesContext.responseComplete();  
      }